Removal of Carbamazepine onto Modified Zeolitic Tuff in Different Water Matrices: Batch and Continuous Flow Experiments

Abstract

Carbamazepine (CBZ) is the most frequently detected pharmaceutical residues in aquatic environments effluent by wastewater treatment plants. Batch and column experiments were conducted to evaluate the removal of CBZ from ultra-pure water and wastewater treatment plant (WWTP) effluent using raw zeolitic tuff (RZT) and surfactant modified zeolite (SMZ). Point zero net charge (pHpzc), X-ray diffraction (XRD), X-ray fluorescence (XRF), and Fourier Transform Infrared (FTIR) were investigated for adsorbents to evaluate the physiochemical changes resulted from the modification process using Hexadecyltrimethylammonium bromide (HDTMA-Br). XRD and FTIR showed that the surfactant modification of RZT has created an amorphous surface with new alkyl groups on the surface. The pHpzc was determined to be approximately 7.9 for RZT and SMZ. The results indicated that the CBZ uptake by SMZ is higher than RZT in all sorption tests (>8 fold). Batch results showed that the sorption capacity of RZT and SMZ in WWTP effluent (0.029 and 0.25 mg/g) is higher than RZT and SMZ (0.018 and 0.14 mg/g) in ultrapure water (1.6–1.8 fold). Batch tests showed that the equilibrium time of CBZ removal in the WWTP matrix (47 h) is much longer than CBZ removal in ultrapure water. The sorption capacity of RZT & SMZ in WWTP effluent (0.03, 0.33 mg/g) is higher than RZT and SMZ (0.02 and 0.17 mg/g) in ultrapure water (1.5–2 fold) using column test. This study has clearly demonstrated that the performance of RZT and SMZ is more efficient for the removal of CBZ from realistic wastewater than ultrapure water. It is evident that the surfactant modification of RZT has enhanced the CBZ removal in both matrices.

Adsorption of Carbamazepine in All‐Silica Zeolites Studied with Density Functional Theory Calculations**

“…[31] In addition to the above studies, which considered hydrophobic high-silica zeolites, other authors have investigated CBZ adsorption in cation-exchanged FAU-type zeolites having an intermediate Si/Al ratio of 2.8, [36] and onto pristine and surfactant-modified zeolite-rich tuffs. [37] Rather low CBZ uptakes were reported in both cases.…”

“…Besides studies of individual zeolites, granular composite materials consisting of crystallites of different zeolites (high‐silica BEA, MFI, and MOR) held together by a clay‐based binder have also been considered [31] . In addition to the above studies, which considered hydrophobic high‐silica zeolites, other authors have investigated CBZ adsorption in cation‐exchanged FAU‐type zeolites having an intermediate Si/Al ratio of 2.8, [36] and onto pristine and surfactant‐modified zeolite‐rich tuffs [37] . Rather low CBZ uptakes were reported in both cases.…”

Mineral Composition and Structural Characterization of the Clinoptilolite Powders Obtained from Zeolite-Rich Tuffs

“…Many studies have been published on surfactant-modified zeolites as organic [38,39] and inorganic [37,40,41] toxicants adsorbents. Several studies [40][41][42][43] suggested that among the many surfactants, the hexadecyl-trimethylammonium bromide (HDTMA) is the most widely applied as an agent that can enhance the ability of zeolites to adsorb the organic pollutants by increasing zeolite hydrophobicity. In more recently published studies, Fuss et al [44] investigated the chemical (acid, basic) and thermal methods for zeolite activation regarding the capacity of natural zeolites to adsorb the odors and toxic compounds.…”

Adsorption of Carbamazepine in All-Silica Zeolites Studied with Density Functional Theory Calculations

“…In addition to the above studies, which considered hydrophobic high-silica zeolites, other authors have investigated CBZ adsorption in cation-exchanged FAU-type zeolites having an intermediate Si/Al ratio of 2.8, 33 and onto pristine and surfactant-modified zeolite-rich tuffs. 34 Rather low CBZ uptakes were reported in both cases.…”